hadrian: Ensure that settings is regenerated during bindist installation

Previously Hadrian would simply install the settings file generated in the build environment during the binary distribution installation. This is wrong since these environments may differ (e.g. different cc versions).

We noticed on Darwin when installation of a binary distribution produced on a newer Darwin release resulted in a broken compiler due to the installed settings file incorrectly claiming that cc supported -no-pie.

Fixing this sadly requires a bit of code duplication since settings is produced by Hadrian and not configure. For now I have simply duplicated the settings generation logic used by the Make build system into Hadrian's bindist Makefile.

Ultimately the solution will probably involve shipping a freestanding utility to replace configure's toolchain probing logic and generate a toolchain description file (similar to settings) as described in #19877 (closed).

Fixes #20253 (closed).